Transcript Document

• Discuss the major characteristics of the four
Biosafety Levels.
• Define “Risk Group” and give an example of
each.
• Discuss how Risk Groups are used in
conjunction with risk assessment to set
Biosafety Levels.
• Assignment of agent based on risk
assessment
• Depends on agent and conditions of use
• Requires professional judgment
World Health
Organization
National Institutes
of Health
• Suitable for work involving well-characterized agents not
known to consistently cause disease in immunocompetent
adult humans
• minimal potential hazard to laboratory personnel and the
environment.
• laboratories are not necessarily separated from the
general traffic patterns in the building.
• Work is typically conducted on open bench tops using
standard microbiological practices.
• Special containment equipment or facility design is not
required,
• Laboratory personnel must have specific training in the
procedures conducted in the laboratory and must be
supervised by a
scientist with training in microbiology or a related science.
Biosafety Level 1
• Builds upon BSL-1
• BSL-2 is suitable for work involving agents that pose
moderate hazards to personnel and the environment.
• Laboratory personnel have specific training in handling
pathogenic agents
• Personnel are supervised by scientists competent in
handling infectious agents and associated procedures
• Access to the laboratory is restricted when work is being
conducted
• all procedures in which infectious aerosols or splashes
may be created are conducted in biological safety
cabinets (BSCs) or other physical containment
equipment.
Biosafety Level 2
• Is applicable to clinical, diagnostic, teaching, research, or
production facilities where work is performed with indigenous or exotic
agents that may cause serious or potentially lethal disease through
inhalation route exposure.
• Laboratory personnel must receive specific training in handling
pathogenic and potentially lethal agents
• Must be supervised by scientists competent in handling infectious
agents and associated procedures.
• Biosafety Level 2 plus all procedures involving the manipulation of
infectious materials must be conducted within BSCs, or other
physical containment devices
• Personnel wear additional appropriate personal protective equipment
including respiratory protection as determined by risk assessment
• A BSL-3 laboratory has special engineering and design features.
o Directional air flow
Biosafety Level 3
• Required for work with dangerous and exotic agents that pose a high
individual risk of life-threatening disease, aerosol transmission, or
related agent with unknown risk of transmission.
• Agents with a close or identical antigenic relationship to agents
requiring BSL-4 containment must be handled at this level until
sufficient data are obtained either to confirm continued work at this
level, or re-designate the level.
• Laboratory staff must have specific and thorough training in handling
extremely hazardous infectious agents.
• Laboratory staff must understand the primary and secondary
containment functions of standard and special practices, containment
equipment, and laboratory design characteristics.
• All laboratory staff and supervisors must be competent in handling
agents and procedures requiring BSL-4 containment.
• Access to the laboratory is controlled by the laboratory supervisor in
accordance with institutional policies
• Two types of laboratory providing absolute separation of the worker
from the infectious agents
o
o
Suit Laboratory
Cabinet Laboratory
Biosafety Level 4
CDC/NIH Guidelines
Biosafety Levels
(www.cdc.gov)
BSL-1
BSL-3
Lower Risk
BSL-2
Higher Risk
• Pathogenicity of the agent
• Modes of transmission and host range of
organism
• Local availability of preventive measures
• Local availability of effective treatment
World Health
Organization
National Institutes
of Health
World Health
Organization
National Institutes
of Health
World Health
Organization
National Institutes
of Health
• High individual risk, low community risk
• Pathogen usually causes serious human or
animal disease but does not ordinarily spread
to others
• Effective treatment and preventive measures
are available
World Health
Organization
National Institutes
of Health
• High individual and community risk
• A pathogen causes serious human or animal
disease; readily transmitted from one
individual to another
• Effective treatment and preventive measures
are usually not available
World Health
Organization
National Institutes
of Health
Risk
Group
1
2
Biosafety Level Laboratory Type
Laboratory
Practices
Safety
Equipment
Basic –
Basic teaching,
Biosafety Level research
1
GMT
None; open
bench work
Basic –
Primary health
Biosafety Level services;
2
diagnostic
services,
research
GMT plus
protective
clothing,
biohazards
sign
Open bench
plus BSC for
aerosols
World Health
Organization
National Institutes
of Health
Risk
Group
3
4
Biosafety Level
Laboratory Type
Laboratory
Practices
Safety Equipment
Containment- Special
Biosafety Level diagnostic
3
services,
research
Level 2 + special
clothing, access
control, directed
airflow
BSC and/or
other primary
devices for all
activities
Maximum
Dangerous
Containment – pathogen units
Biosafety Level
4
Level 3 + airlock
entry, shower
exit, special
waste disposal
Class III BSC, or
positive
pressure suites
with class II
BSCs, double
ended autoclave
World Health
Organization
National Institutes
of Health